


Three of a Kind

by in_motu_proprio



Category: Marvel Cinematic Universe
Genre: Bottom Tony Stark, Double Penetration, Established Relationship, F/M, M/M, Multi, Threesome - F/M/M
Language: English
Status: Completed
Published: 2020-05-18
Updated: 2020-05-18
Packaged: 2021-03-03 00:55:51
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,272
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24246130
Author URL: https://archiveofourown.org/users/in_motu_proprio/pseuds/in_motu_proprio
Summary: This takes place sometime before Civil War.  Tony's been a good boy and gets to invite a third into their bed.  Natasha was expecting a bubble headed beauty.  Instead she gets someone entirely different and unexpected.
Relationships: Natasha Romanov/Tony Stark, Steve Rogers/Natasha Romanov/Tony Stark, Steve Rogers/Tony Stark
Comments: 3
Kudos: 68





	Three of a Kind

“When you said you were getting a third, this isn’t what I was imagining,” Natasha told Tony as she stood there staring at their third for the night. Natasha had come to Stark Tower tonight figuring that there would be some beautiful airhead waiting to make Tony’s fantasies of two women on him at once a reality. Instead, what stood before her was a tall drink of muscular water waiting for her to give him a chance to speak. “Whose ass is he for, mine or yours,” she teased.

“Por qué no los dos,” Tony asked as he walked around Natasha, a hand sliding over her lower back. “Why choose?” 

“Tony invited me after a mission we did in Berlin. I just finally worked up the courage,” their guest said shifting from one foot to another. 

“I’d offer you a drink to calm your nerves but I don’t think his whole bar would do it,” Natasha teased as Steve looked at her with those wide, sad eyes of his. Instead of calming his nerves, Natasha decided to up the ante and leaned in to kiss Steve right on the mouth, knowing Tony’s eyes would be stuck to her. Steve was stiff at first but relaxed into it slowly, kissing her back with gusto. Steve turned out to be a pretty good kisser and Natasha let herself get carried away. She felt Tony move in behind her, pressing close and running his lips over her neck. 

Natasha reached back to stroke Tony’s hip, pulling him in close so he could rub against her hip like he liked. She came up for breath, pulling back enough so there was a clear shot between Steve and Tony. They did not disappoint, going for each other like men who’d been thinking about just this moment for way too long. Watching Tony and Steve kiss was sexy as hell and Natasha rubbed a hand over her throat as she watched, fixated on the way Steve took Tony’s face in hand to keep him in line. It was a move Natasha had had to employ more than once. Tony could be a handful. 

When they broke apart it was nearly as though they were on the same brain wavelength, as they both turned for Natasha, overwhelming her with hands and mouths that only wanted to please her. By the time she was able to refocus, Natasha realized that someone had unzipped her dress. Someone else had unpinned her hair, and who knew how her panties were already on the floor. No she knew, that was Tony. Steve wouldn’t have been so bold. Or maybe it was just her own reaction to all of this. “Let’s go to bed,” Tony suggested, his hand cupping Natasha’s ass while the other cupped Steve’s. Tony was in heaven and Natasha was glad for him. It turned her on that he was turned on. 

They headed in the direction of bed, pausing a few times to kiss or grope each other but generally making forward movement toward the bed. Tony touched down first, kneeling up as he went for Steve’s shirt. “There are too many clothes for this to be a threesome,” he teased tugging at Steve’s shirt until it was on its way up over Steve’s head and onto the floor. “Jesus Christ,” Tony groaned, swallowing thickly. Natasha read his mind and they both leaned in to worship at the shrine of Steve’s chest for awhile. He focused mostly on Steve’s nipple while Natasha focused on the cut of his pectoral muscle. 

They turned on her next, tugging at her dress until it was a pool of fabric on the ground. Their clothes went like that for awhile until there were no more clothes left to strip off of people, just bodies and beautiful ones at that. They’d talked about including a third for awhile, kind of on and off. It never occurred to her that they hadn’t discussed a gender let alone a specific person. If she were a jealous woman she might have found the kisses Steve and Tony were exchanging to be too familiar, too intimate. Instead she reached down the front of Tony’s body to take his cock in hand and pump it a few times. 

“You’re beautiful, Natasha,” Steve told her as he leaned in to run his mouth over her breast. Tony joined in on the other and for awhile she had the pair of them there on her, covering almost every inch of her body with theirs. It was intoxicating and she urged them to stay, petting their hair, groaning when Tony’s hand wrapped around Steve’s cock and pumped a few times. 

Steve was _big_ and Natasha couldn’t help but look forward to that. Tony wasn’t small, but she’d use the word average. Average was fine, average got the job done and Tony had always been eager to please her orally, one of Natasha’s favorite parts of the sex act. “He doesn’t bottom often, and not that big as long as I’ve been fucking him,” Natasha told Steve as her and Tony’s hands wrapped around the man’s prick, rubbing up and down in a slow, solid rhythm. 

“Has that been long,” Steve asked. 

“…” Natasha looked at Tony who shrugged clearly not caring if Tony knew their history. “A few years,” she confessed feeling strange being so honest about it. 

“When he invited me I thought…” 

“You thought it would be Pepper,” Natasha guessed. 

“I did. I’m pleased it’s you.” His fingers wrapped around her throat gently, urging her closer as he leaned in to kiss Natasha breathless. He picked the moment Tony decided to drop low and use his mouth on her. She just spread her legs and let him move in closer, getting smothered by Natasha as she rode down into Tony’s face while Steve kissed her. 

“When he talked about a third, I was imagining someone female,” she told Steve with a laugh, resting a hand low on Tony’s stomach as the man devoured her folds. “I’m pleased it’s you,” she said breathlessly, echoing his words.  
It went fast from there, Steve slid in behind her with slick fingers, Tony having pulled the lube out and left it on the bedside table before all this started. With Steve at her back, Natasha chanced leaning back to enjoy the solid strength of Steve Rogers behind her. He slid a finger into her asshole like it was nothing, kissing his way up her neck as he did, murmuring how good she was going to feel. Natasha idly wondered how long it had been for Steve and if he’d thought of it as much as she had since D.C.

She came for Tony a few minutes later, two of Steve’s fingers up her backside. All of it was a little overwhelming and Natasha fought to keep on top of her emotions so the boys wouldn’t notice just how much this was getting to her. “Tony… God…. ok… ok…. stop,” she laughed having to actually climb off of Tony to get him to stop for her. “Always eager to please,” she teased leaning down to kiss his messy face. “Now sit up against the head of the bed.” 

Steve was hard enough but Tony wasn’t yet and Natasha planned on taking advantage of that. She bent over Tony, wrapping her mouth around him to suck her lover’s cock. Years ago she couldn’t admit that, that Tony was her lover and yet here they were now, eagerly appreciating a third together. “Fuck me,” Natasha urged to Steve when she came up for a breath. Steve didn’t have to be told twice and moved in behind Natasha fast, positioning himself at her entrance. 

His cock slipped through her folds a few times, grazing her clit, before he lined things up and pushed home inch by agonizing inch. Natasha had to come up for air on Tony as it was but this was stealing any breath she might have had. “… Jesus he’s big,” Natasha told Tony, leaning forward to kiss his stomach as she took Steve into her body. She found herself breathless and stretched farther than she had been in some time. It was good, though, a nice deep stretch that was going to linger long after both her men were on their way to do something else heroic and/or stupid. 

He surprised her with two slick fingers at her backside while his hips were pumping away in a slow rhythm. Natasha tried to relax but it was hard when she was surrounded by sex. “My God,” she moaned, twisting down onto the intruding fingers. It felt lovely to be stretched this way by Steve and she focused on that as she sucked Tony hard. 

“I need you,” Tony told her. 

He was stiffening up nicely, his body responding to Natasha’s mouth and hands lavishing all that attention on him. “I need you,” she echoed, squeezing down around Steve as he moved in her, two fingers in her asshole turning to three pretty rapidly and Natasha couldn’t help but think that this was not Steve Rogers’ first rodeo. “Steve,” she said softly, “I’m going to get on Tony now. Give me a minute to adjust then you can try.” 

Tony was breathless and laser focused on her every movement as Natasha climbed his body and straddled his waist. Steve kept three fingers in her backside as she did, staying close enough that she could feel his breath on her skin. Steve was bigger than Tony and taking them both was going to be a challenge, but probably a good one she told herself as she sunk down on Tony’s cock in one go, watching his eyes roll up in his head. “Perfect,” Tony told her as she bottomed out on top of him, twisting her hips down until there was nowhere he could go. 

“Lean forward,” Steve urged surprising the hell out of Natasha when he leaned in and licked around the intruding fingers then around the intruding cock. She felt lightheaded and wobbly as his fingers slid from her body and she felt him replace it with a cock that was on the bigger side of her experience. Natasha took a deep breath and pushed herself down on him, feeling the failed first and second attempt with a wince before the third resulted in him penetrating her and getting a couple inches in before Natasha had to put a hand on his chest to pause him, breathing hard as her body tried to figure out which way was up. 

“My God,” Natasha breathed, reaching behind to feel first where Tony was then Steve. “Keep going,” she urged Steve. Tony was pretty well frozen underneath her, moaning deeply as Steve found his way into Natasha’s willing body. “Wait until he has you,” Natasha told Tony. “He’s so big.” They kissed as Steve advanced, the man’s hands dividing their attention between Natasha and Tony’s chests. 

Everything felt slightly askew and Natasha believed the colloquial term was: _dick drunk_. It felt so good to have the two of them in her she was on the verge of cumming right then and there. It didn’t help her self control that the two of them were groaning and otherwise making lots of noise as they felt each other move through that thin layer of tissue. Natasha leaned back into Steve who held her tenderly so Tony could lean up and suck on one breast then the other adding obscene sucking noises to the the cacophony they were creating. 

Natasha’s hands landed on Tony’s chest, muscle memory leading them to sit wide to allow for an arc reactor that wasn’t there anymore. Steve’s hand ran down her stomach in a straight line to her clit, giving it a little attention. That was literally all Natasha needed in that moment to fly over the edge into orgasm, calling out both their names as she did. Lights exploded behind her eyes and Natasha thought she might have entirely forgotten how to breathe. Things stayed intense for a good, long while as these things went, Natasha finally batting Steve’s hand away when she couldn’t take any more. 

“Don’t either of you move yet,” she warned, cheek pressed to Tony’s chest. 

“You ok,” Steve asked with genuine concern.

“Just holding onto the moment,” Natasha told him as she slowly peeled herself up off of Tony’s chest. “Now I could go again,” Natasha pointed out, “but I feel like I’d be cheating Tony out of something quite fun.” 

Steve leaned in, kissing her shoulder, “I can go again in five minutes.” 

“God Bless Super Soldier Serum,” Tony quipped from below, rocking up into Natasha. 

She took what they had to offer with a smile on her face because Natasha really was having a hell of a time. Steve held her firmly, one arm around her middle the other positioned so he could touch her breasts. And that sweet cupid’s bow mouth of his ran over her shoulders and neck like he was old hand at pleasing women. And maybe he was. He had traveled with the USO girls for how long? He couldn’t have been celibate that entire time, right? 

“I’m close,” Tony announced, his hands kneading Natasha’s ass. 

“Go ahead.” 

“You’re sure,” Tony asked. Natasha rarely let him cum inside her, usually preferring he finish on her stomach or backside. 

“You deserve it,” she told him caressing his face. Tony came undone then, finishing deep inside Natasha. “You too,” she told Steve, caressing his hip with her free hand. Steve seemed to just have needed her permission, cumming moments later with a soft sigh against her shoulder. Natasha, filled to the brim, just laid there and breathed for a few seconds, gathering herself for what was always an undignified act… pulling out. 

The boys were thankfully quite helpful, Tony grabbing the wipes out of the nightstand drawer as Steve kept her busy with a kiss. Everyone cleaned up and laid there for a minute, appreciating the size of the bed that she could be surrounded by two full grown men and not feel dwarfed. She felt safe, though, that was for damn sure. Natasha didn’t feel safe often so she took advantage stretching out between them and letting the pair of them clean her up and coo after her for a little while. 

“You need some water,” Tony asked as he handed off a bottle. It took Natasha a moment to realize it was a bot bringing in that water though it wasn’t the first time Tony had done that. He preferred the bots to people most days in Natasha’s estimation and she didn’t know if she disagreed. She took the bottle with a nod, uncapping it and having about half the bottle before offering it to Steve. He had a bit then capped it, Tony having gotten his own water from the bot. “You were glorious,” Tony told Natasha with a kiss to her shoulder. 

“You boys weren’t so bad yourselves,” she teased running her hand down Steve’s chest. “You were being serious that it only takes you five minutes, right?” 

“I was,” Steve chuckled, leaning into the hand at his chest.

“Good, I can’t wait to see you fuck him.” Natasha smiled sweetly, a contrast to the words coming out of her mouth just to watch Steve squirm a little bit. 

“Tony,” Steve asked seeing if he felt the same way. 

“Oh I’ll be happy to bottom for a cock like that,” Tony said smiling wickedly. 

“Then get over here and get to work,” Steve commanded. 

Natasha didn’t think she’d seen Tony smile wider than that in a long time. Tony crawled across the bed to settle in Steve’s lap. “Kiss me first.” There was a vulnerability to Tony that came out sometimes during sex and needing to be acknowledged as who he was first was important. Tony had been in a lot of nameless sex situations and it had taken its toll on him in Natasha’s estimation. The boys kissed a slow, sweet kiss, Steve’s hands caressing Tony’s backside boldly while Natasha lay and watched. 

“You two look good together,” Natasha told them when they broke apart, her hand sliding between their bodies to find the first dick she could, Steve’s. She gave it a couple of strokes before running her hand up over his stomach. God he was well-muscled, she thought as she leaned in to drag her tongue across the groves of his abs. She turned to Tony a minute later, “you should suck him.” 

“On my to do,” Tony agreed leaning in to kiss Natasha. She moved in behind Steve, kneeling behind him as Tony knelt in front of him. Her hands caressed Steve’s back and chest as Tony leaned in and took him down halfway his first attempt. 

“Don’t rush, we’ve got all the time in the world.” Technically they had until tomorrow afternoon, but in sex terms that was a lot of time. She pinched one of Steve’s nipples getting an unexpectedly enthusiastic groan from him. “He likes a little pain with his pleasure then,” Natasha asked doing it again and getting the same result.

“My chest is just sensitive.” Tony reached up to the other nipple and together he and Natasha pinched them both watching Steve’s cock jerk in reaction. “God,” Steve groaned leaning back into Natasha. They played with Steve’s chest as Tony sucked his cock, pushing Steve almost to the edge in short order. “Wait… hold… I need a second,” Steve warned as they worked in tandem on his body. 

“Too much,” Tony asked on a rare moment of grabbing a breath. He looked up at Steve and Natasha. “Man I’d kill for a camera about now. You two look hot together.” 

“You were driving,” Natasha reminded with a gentle stroke over Steve’s throat “I think we should get him ready,” she whispered in Steve’s ear. To be fair, the whole time Tony had been sucking him, Steve had been playing with Tony’s ass working one spit slick finger into his ass before he’d had to call pause. “He’s going to need a lot more than one finger if he’s going to take that.” Natasha reached around and gave Steve a playful squeeze. 

“Agreed,” Steve laughed, peeling himself from Natasha’s embrace as they both looked down predatorily at Tony. Tony actually looked a little taken aback by the pair of them focused on him wholly. “Lay on your stomach, Tony. Get comfortable.” 

Natasha helped him with a pillow under his hips and another sip of water to wet his whistle after all that cock sucking. “Good,” Natasha asked with the faintest of smiles. 

“So good,” Tony agreed. It was then that Steve decided to shock them both and bent over Tony, bringing his lips to Tony’s ass. He worked his way in, both hands spreading Tony’s cheeks as he made a meal out of the man. Tony’s face told the whole story and Natasha held onto him, caressing his face and running her fingers through his hair as Steve worked. Tony cursed … a lot, and today was no exception. He writhed back into Steve, reaching back with one hand to encourage the man, his fingers sinking into Steve’s hair. And wasn’t that beautiful, Natasha thought, Tony looking back at their third with such fondness. The whole reason she’d suggested a third was as a reward to Tony for holding himself together, so it was wonderful to see that her assessment of his needs had been spot on. 

“Jesus fucking Christ Rogers…” Tony turned his cheek to press it to Natasha’s chest, letting her hold him a little closer. “I could lay here and take this all day long but maybe we ought to move onto the lube,” Tony finally said long after Natasha was sure Steve’s jaw was clicking. The man had been relentless and so very eager. Natasha liked both those qualities about Steve Rogers. And because she liked him, she slid out from under Tony and fetched the lube, bringing back the little pump bottle with a smile. “It’s his favorite lube,” she told Steve. 

“The orange scented one,” Tony asked. 

“Yeah,” Natasha carded her fingers through Tony’s hair backward. “Pepper sent it over last week.” The woman was in the know about Natasha and Tony and didn’t object so long as they were discreet. As it was, she had her own fascination with a couple of men in Stark Industries. Natasha wasn’t sure if Pepper had dabbled yet, but she certainly hoped she had. 

“She knows?”

“Pepper knows everything,” Tony said as Steve used slick fingers to caress his hole. He went around a few times before Natasha saw that telltale wince that said he’d been penetrated. “This is the most faithful I’ve ever been,” Tony pointed out. 

“It is,” Natasha agreed watching as Steve’s arm started to move. “Only two women and the occasional third,” she said giving Steve a once over. Steve seemed to understand but not get how a woman could be so open to her man cheating yet his fingers remained up Tony’s ass. “Open relationships are something you might want to look up,” she told Steve who she could see commit it to memory. 

More lube was added along with a third finger and as Tony focused on that a lot of the conversation was stilled. Natasha had come to kneel in front of Tony, letting him touch her however he’d like as he was slowly opened up by a man who knew an awful lot about anal sex for being a transplant from the 40s. Steve was gentle but firm in his pursuit of Tony’s openness, working the three fingers in and out, getting the most delicious moans out of Tony as he did. “Is it good?” 

“So good,” Tony told her as he leaned in to kiss Natasha. “I think I’m ready,” he told them both, looking back at Steve with some worry in his eyes at spotting Steve’s cock. 

“Let me work a little more then you will be,” Steve told Tony leaning in to kiss his hip as more lube was added and another finger. 

Tony pulled the pillow out from under his hips and looked at Natasha. “I want to be with you when he pushes into me.” She didn’t need to be asked twice and shifted under Tony until they were lined up. He was hard from all the attention to his ass so it took very little, essentially just lining up, to push home into Natasha. Tony closed his eyes and Natasha cupped the back of his head to her chest as she watched Steve shifting. He was slicking his cock, getting ready and she could feel Tony tensing. She caressed his back, his hips, his chest as she tried to calm him. 

Tony let out a soft, disgruntled sound and she knew that things were happening. “Breathe,” Natasha told him. “Breathe.” She caressed Tony’s face as Steve started to push into him, watching the war between pleasure and pain on Tony’s face. She squeezed around him, reminding him he had something fuck. Tony’s hips moved a little erratically as he tried to have her while being taken. Eventually he had to still and let Steve do his work, pushing into Tony in slow advances. “That’s it. That’s the hardest part,” she told him after Steve had managed to push halfway in. 

“How did you take both of us,” Tony asked seriously, sweating a little around the hairline. 

“Very carefully,” she answered without answering, wiping a bit of that sweat away. “How does it feel?” 

“Enormous,” Tony said honestly, reaching back to test the progress. “He’s only halfway in. Jesus. Keep going. I want to feel it all,” Tony told Steve. Natasha could see next to nothing from her vantage point underneath Tony but she could certainly feel her lover wiggling and whimpering when things got a little tight. “Is that… are you fully in now,” Tony asked Steve reaching back to check and finding that he was in fact all the way in. “Wow.” 

“Wow is a good word for it,” Natasha said leaning in to kiss Tony softly on the forehead as Steve started to move. He was moving inside Tony but every move in Tony made Tony move in Natasha. It didn’t take long for Steve to have them both moaning his name, Natasha’s hand finding that sensitive nipple to give it a pinch in thanks. “Let Tony move between us,” Natasha suggested watching Steve shift back a little bit as Tony started. 

It was slow at first, fucking into Natasha and almost off of Steve’s dick or fucking himself back into Steve’s dick and almost out of Natasha. He was torn between the two and moved like a man who was having a struggle, back and forth between the two of them getting some good moans from Natasha and Steve for all his trouble. “I can’t… I’m l… I’m close,” Tony warned them and Steve took over, moving into Tony like he owned the man’s body in that moment. And, hell, maybe he did. 

“Steve!!!” Tony reached back and grabbed the man’s hips as he came, grinding himself back into Steve and painting Natasha in seed as he came. Steve kept up the thrusting, pushing every drop of seed that he could out of Tony. Natasha kissed his shoulder, his jaw, before finally kissing Tony again. Steve was polite and finished pretty quickly after that, leaving them in a mess of limbs on the California King.


End file.
